干旱胁迫下水杨酸和内生真菌对多年生黑麦草的影响  

Effects of salicylic acid and Epichloё on perennial ryegrass (Lolium perenne) under drought stress

作　　者：马碧花 蔺伟虎 高敏 王兴迪 田沛[1] MA Bi-hua;LIN Wei-hu;GAO Min;WANG Xing-di;TIAN Pei(State Key Laboratory of Grassland Agro-ecosystems,Key Laboratory of Grassland Livestock Industry Innovation,Ministry of Agriculture and Rural,College of Pastoral Agriculture Science and Technology,Lanzhou University,Lanzhou 730020,China)

机构地区：[1]兰州大学草地农业生态系统国家重点实验室兰州大学农业农村部草牧业创新重点实验室兰州大学草地农业科技学院

出　　处：《草业学报》2020年第1期135-144,共10页Acta Prataculturae Sinica

基　　金：国家自然科学基金(31502001);国家973项目(2014CB138702)资助

摘　　要：本试验研究了温室盆栽条件下带内生真菌(E+)和不带内生真菌(E-)的多年生黑麦草喷施不同浓度水杨酸(SA)后,持续干旱胁迫15 d和对照水分两种条件下,多年生黑麦草的叶片相对含水量(RLWC)、叶绿素含量(Chl)、过氧化物酶(POD)活性、超氧化物歧化酶(SOD)活性、丙二醛(MDA)含量、脯氨酸(Pro)和可溶性糖(SS)含量等生理指标的变化,以明确干旱胁迫下SA和内生真菌对多年生黑麦草的影响。结果表明,在干旱胁迫下,感染内生真菌的多年生黑麦草叶片相对含水量、叶绿素含量、POD活性、SS含量显著(P<0.05)高于未感染内生真菌的多年生黑麦草植株;一定浓度的SA增加了多年生黑麦草叶片相对含水量、叶绿素含量、POD活性、SOD活性、Pro和SS含量,降低了MDA含量,且最适水杨酸浓度为0.25和0.50 mmol·L-1;内生真菌与SA互作显著(P<0.05)提高了多年生黑麦草SOD活性、POD活性和叶绿素含量。该结果说明内生真菌与SA都能提高多年生黑麦草的抗旱性,即内生真菌和SA通过提高寄主的渗透调节和活性氧清除系统进而提高了寄主的抗旱性。This greenhouse experiment studied the effects of different concentrations of salicylic acid(SA)on endophyte-infected(E+)and endophyte-free(E-)perennial ryegrass(Lolium perenne),under continuous drought stress for 15 days or well watered(Control).Measurements included leaf relative leaf water content,chlorophyll content,peroxidase(POD)activity,superoxide dismutase(SOD)activity,malondialdehyde(MDA)content,proline(Pro)and soluble sugar(SS)of the perennial ryegrass.Changes in physiological indices such as SS content were examined to determine the effects of SA and endophytic fungi on perennial ryegrass under drought stress.It was found that the relative water content,chlorophyll content,POD activity and SS content of E+were significantly higher(P<0.05)than those of E-L.perenne plants under drought stress.The addition of exogenous SA increased the relative water content,chlorophyll content,POD and SOD activities,and Pro and SS contents,while decreasing MDA content.The present study showed that exogenous SA solutions of 0.25 and 0.50 mmol·L-1 were best for enhancement of the drought tolerance of L.perenne.There was a significant(P<0.05)interaction effect between Epichloёendophyte and SA together on SOD activity,POD activity and chlorophyll content of perennial ryegrass.In summary,Epichloёendophyte and SA both improved the drought resistance of perennial ryegrass.Specifically,Epichloёendophyte and SA promoted osmotic adjustment and activity of oxygen radical scavenging system,and thereby increased the drought resistance of the host plant.

关 键 词：多年生黑麦草 内生真菌 水杨酸 干旱胁迫 

分 类 号：S543.6[农业科学—作物学]